The purpose of this program is to develop instrumentation and techniques for automated cytology of exfoliated urinary bladder epithelium, to be used in the detection and diagnosis of bladder carcinoma. Additional goals include the use of this instrument system to provide an automated, objective method of grading bladder tumors, to monitor the effects of intravesical and systemic chemotherapy on exfoliated epithelium of bladder tumors, to evaluate the effect of chemotherapeutic agents on the cell cyclie kinetics of bladder tumor cells in vitro and in animal systems, and to quantitate the immunoreactive state of lymphocytes in regional lymph nodes draining the bladder. The flow cytometry system and cytochemical staining methods developed by us permit simultaneous measurements of total DNA and RNA per cell, as well as cellular and nuclear size. In addition, we have developed techniques using the fluorescent dye acridine orange as a molecular probe to identify qualitative differences in chromatin conformation that are believed responsible for the characteristic "texture" of cancer cell nuclei. Thus, all of the cellular features known to distinguish malignant from benign bladder epithelial cells can be translated into a "machine readable" form for quantitation by flow cytometry. Suspensions of exfoliated epithelial cells from 50-100 patients with bladder tumors will be collected by bladder irrigation and studied by the methods outlined above. As these cases are examined, cytometric data will be compared with histologic findings, and modifications of the staining procedure carried out to optimize results. This will be concerned primarily with the various possible ways to demonstrate qualitative differences in chromatin structure, which is believed to be the most sensitive descriptive feature of the cell. In addition, instrumental changes will be implemented to increase the precision of measurements, to increase the number of features measured for each cell, and to increase the data handling capacity to deal with large numbers of cells. Parallel studies will be carried out using the same basic methods to accomplish the additional goals listed above.